It's all about Artemis in and around Cape Canaveral. Colorful hand-painted placards proclaim "Go Artemis!" There are large temporary street signs. There is a lot of chatter about NASA's flagship human space exploration program.
In the days before NASA attempted to launch its Artemis I mission, the first test of a megarocket called the Space Launch System (SLS), NASA declared that they were going. NASA has a plan to return humans to the moon and eventually send them to Mars.
The SLS has to leave this planet. The Kennedy Space Center was the location for the first two launch attempts. The next attempt is expected to take place on September 27 with a possible backup date of October 2.
Daniel Dumbacher is the executive director of the American Institute of Aeronautics and Astronautics and oversaw the initial development of the SLS. I don't worry about this at all. The bigger picture is that we are reestablishing the launch capability that we lost after Apollo.
As agency officials work on the rocket, they are quick to reiterate that Artemis I is a test flight and a risk. Even though the rocket is based on space-shuttle-era technology, it is still a new machine. The spaceship on top is new as well. If all goes well, the SLS will launch the uncrewed Orion capsule onto a looping journey around the moon, which will precede a crucial test of the craft when it attempts to survive a fiery high-speed return to Earth.
There are high stakes. The pair have eaten $43 billion in taxpayer dollars and are over budget. NASA's troubles launching this rocket aren't unexpected but for a different reason
Garver is a well-known critic of the Artemis hardware. One of the reasons is that they locked them into this design that wasn't focused on operability.
As a result of political pressure from influential congress people such as Bill Nelson, the SLS and Orion were built with parts built by multiple legacy companies. The result is an unwieldy contraption relying on dated technology that is jokingly referred to as the "Senate Launch System" and that is projected to cost around $4 billion per launch. The SLS will not be recovered even if it leaves the launchpad. Either it will be dumped in the ocean or left in space.
Since NASA rolled the SLS to the pad on August 16th, five rockets have been launched from Cape Canaveral by the company. Depending on the specific mission profile and final orbital destination, the Falcon Heavy can hoist about two thirds as much as the SLS, with each launch priced at approximately
The companies who had expertise in these rockets wanted to keep the business, which meant convincing the policy makers to design it this way. Taking expensive parts of past programs and putting them together differently would be easy and cheap.
The evening before the first launch attempt, which was scheduled for 8:33 A.M., was already crowded with tens of thousands of sightseers and hundreds of stressed out space journalists. All eyes were on the SLS and Orion, stacked together as a 322-foot- tall white-and-ochre statue gleaming in floodlights at the Launch Complex 39, where the multihour process of fueling the rocket would soon begin. As the night went on, troubles began to roll in, just as reliably as the rainstorms that ruin Florida's overwatered lawns each afternoon.
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The weather delayed. The team couldn't start fueling the rocket because of the high chance of a lightning strike. The storms moved out of range after about an hour. Liquid oxygen and liquid hydrogen are pumped into the main stage tank. Cryogenic propellants are very dangerous and delicate to operate.
The same type of issue they encountered during a wet dress rehearsal and the same kind of problem that frequently delayed space shuttle launches were detected at the base of the rocket.
Hydrogen is the lightest atom in the universe and makes an excellent propellant. The molecule can find ways out of things. The challenge with it is that it can be dangerous in certain places.
The leak was plugged. The tanking was continuing. The team members decided that the crack in the foam was not a problem and kept going. It wasn't so cavalier a short time later when they realized one of the rocket's four engines wasn't cooling to the right temperature during a procedure called "chilldown." Normally, teams bleed a small amount of the -423-degree-Fahrenheit propellant through the system to condition the four engines before blast off, but engine number three didn't seem to be responding
That was the one that caught the attention. A scrub was declared by the launch director around 8:40 A.M.
NASA officials said that the chilldown procedure had been going well. Engineers decided that the sensor that reported a high temperature was probably faulty because the team had enough data to suggest that the coolants were flowing well. They wouldn't fix it on a second try. CNN correspondents asked if the plan was to ignore the sensor. SLS chief engineer John Blevins said yes.
The public is not used to seeing problems with the instruments.
There will be a two-hour launch window on September 3. As many as 400,000 people are expected to attend the holiday weekend this year.
The problems kept piling on. There was another hydrogen leak almost immediately after tanking operations began. The leak was too large to be fixed by warming the fill lines and pressingurizing them with helium. The team was behind its time line by 11 A.M. after three failed attempts. The hydrogen tank only had 11 percent of it's capacity.
The Artemis mission manager said that the leak exceeded the flammability limits every time they saw it.
The large hydrogen leak had occurred at the same junction where a manually entered command had produced an "inadvertent overpressurization of the hydrogen transfer line" and boosted pressures to 2 or 3 times higher than they should have been. The seal at that junction may have been damaged by the over pressurization.
The wrong valve was commanded and there was a sequence of about a dozen commands that were required. It may have been the fact that we didn't automate this particular sequence that could have been a factor in the overpressure.
NASA has yet to link that error with the hydrogen leak. The fault tree analysis will point to a root cause of the scrub.
Dumbacher says that they use the data and information they have to determine which fault was most likely to occur. The people are doing all the right things.
Even if the command didn't cause the leak, it's not good news. She says that it is a red flag at this point. At this stage of the game, you don't send commands to over pressurize a line. The procedure is a process. Those are not the kind of questions that should have been automated.
The third launch attempt will be pushed back from September 23 to September 27 because NASA has fixed several seals on the launch pad.
The timing is dependent on two things: a successful repair and tanking test scheduled for September 21, and a waiver from Space Launch Delta 45, a unit of the Space Force that grants permission for all rocket launches on the Eastern Range. Only the SLS was certified for launch. The batteries that power the self-destruct system will need to be reloaded at the Vehicle Assembly Building.
Space Launch Delta 45, whose responsibility is public safety, would need to waive the requirement to launch at the end of September. NASA will have to go back to the VAB and try for a mid- October window if that is not possible.
Dumbacher doesn't think there's an appreciation for how some of the early decisions were constrained by the budget He points to the selection of cryo fuels.
You are not using new tech. The laws of physics have not changed according to Dumbacher. Mother Nature has provided us with what we can use to meet our objectives. It requires a lot of energy to get large systems and large amounts to go to the moon and then onto Mars.
September 12 was the 60th anniversary of President John F. Kennedy's famous speech in which he said, "We choose to go to the moon in this decade and do the other things, not because they are easy."
It has been sixty years since Earth's most venerated space agency was founded, but it is still hard to overcome political forces that keep it on the ground.
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